Screw-wrench



EETTED sTATEs PATENT oE-EICE.

DEXTER H; CHAMBERLAIN, OF BOSTON, MASSACHUSETTS.

SCREW-WRENCH.

specification of Letters Patent No. 10,666,l dated March 2 1", 1854.

To all whom t may concern:

Be it known that I, DEXTER H. CHAM- BERLAIN, of Boston, in the county of Suffolk and State of Massachusetts, have invented a new and useful Improvement in Screw or Coach Vrenches; and I do hereby declare that the same is fully described and represented in the following specification and the accompanying drawings, letters, gnres, and references thereof.

Of the said drawings, Figure l, represents a side view of my improved coach. wrench. Fig. 2, is a vertical and longitudinal section of it. v

In the said drawings, A, denotes the hammer or stationary jaw, and, B, the sliding jaw of the wrench, this latter jaw being made so as to embrace and slide freely on the shank, C, and either toward or away from the hammer jaw. The said shank, C, is formed as represented in the drawingsthat is to say, it is a split, divided or double shank formed of two parts, a, b, united at their lower ends as seen at c. Through the part, c, a shaft or rod, D, is made to eX- tend and to carry on its inner end, a tapering male screw E, which is made to work into a correspondingtapering female screw, F, formed in two parts, 64 b, of the shank as seen in Fig. 2. On the other end of the shaft, D, is a handle H, to which the hand of a person is applied to turn the shaft and to hold the wrench while it yin use. The.

las to cause'the parts `a, b,v of the shank to close `or move toward one another when the tapering screw is being unscrewed. By

screwing inward the tapering screw these parts, 0:, b, are forced asunder by it so as to clamp the movable aw firmly on the shank and at whatever distance it may be from the hammer aw.

The manner in which ymy coach wrench is constructed renders it a very simple, efficient and easily operated instrument, in comparison to many othersV in use.

What I claim as my invention, is,

The improvement of making thek wrench with a split or double shank, a movable aw to embrace and slide on the shank, and `a tapering screw or its equivalent applied to the shank so as to be capable o-f separating the two parts, a, b, of the shank and thereby clamping the movable jaw in place on the shank all substantially as above specied. v

y In testimony whereof I have hereunto set 'l my signature this eighteenth day of February A. D. 1854:.

DEXTER H. CHAMBERLAIN.

Witnesses:

R. H. EDDY, l F. P. HALE, Jr. 

